by applying samplexy to a regional snapshot of model output I got some strange results for sample points outside of the axis limits of the sample field. Please try the attached journal file.
It seems that only good points are filled with interpolated values.
Initialisation of the full output buffer with blanks before interpolation
should be sufficient. Then one will get blanks for outlying co-ordinates.
It would be nice if the author (Ansley Manke) could manage to correct
samplexy.F soon.
Best regards
Torsten Seifert
-- Dr. Torsten Seifert Institut fuer Ostseeforschung Warnemuende (IOW) an der Universitaet Rostock D-18119 Rostock, Seestrasse 15, Germany Phone +49-381-5197-118 Fax +49-381-5197-4812
!! this example shows the malfunction of samplexy occuring for (xpts,ypts)
!! lying outside of the axis limits of the array to sample from
!! direct listing with x+360 gives correct data (applying the modulo x)
!! I would expect samplexy to return missings for unvalid (xpts,ypts)
!! this could be achieved by initialising the return buffer with missings
!! in samplexy.F (interpolation runs obviously only for good (xpts,ypts) there)
!! torsten.seifert@io-warnemuende.de
SET DATA coads_climatology
SHOW DATA coads_climatology
let xv={30, 390}
let yv={60, 60}
let sst_xy=samplexy(sst,xv,yv)
list sst_xy
list sst[x=30,y=60], sst[x=390,y=60]